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问题 填空题

日常生活中常提到的像有：（1）小孔成像；（2）照相机成像；（3）放大镜成像；（4）平面镜成像；（5）电影银幕上的像．其中属于虚像的有______（填序号）．

答案

小孔成像是属于光沿直线传播现象的应用，成的像是倒立缩小的实像，

而照相机成像是凸透镜成像原理，成的像是倒立缩小的实像，

放大镜成像是凸透镜成像原理，成的像是正立放大的虚像，

平面镜成镜是光的反射现象，成的像是正立等大的虚像，

电影银幕上的像是凸透镜成像原理，成的像是倒立放大的实像．

故答案为：（3）（4）．

多项选择题

国际工程咨询市场的特点是( )。

A．市场广泛

B．准确、及时的信息十分重要

C．工程咨询项目有一定的难度

D．采取公开竞争方式选择聘用咨询公司

E．国际工程项目的复杂性与相对高风险性
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单项选择题

Congress makes the laws in the United States. It has two parts, which are more or less equal in power. They are known as the House of Representatives and the Senate. The House of Representatives is larger than the Senate whose 100 members (two from each state) serve for six years. The 435 members of the House are elected every two years, and the number from each state is determined by the population of the state. For example, California, which has a large population, has 43 representatives, while the State of Nevada has only one.
The House and Senate are divided into small groups which take care of special matters such as education or foreign affairs. The most important work of Congress is often done in these groups, which are called subcommittees.

In the U.S. Congress, the House of Representatives and the Senate are______.
A. not equal. The House is more powerful
B. almost equal in power
C. not equal. The Senate is far more powerful
D. different. The House is more important

According to the Constitution of the United States, a senator must be at least 30 years old and he must have been a citizen of the United States for nine years at the time of his election. To be elected to the House a person must be 25 years old and must have been a United States citizen for seven years. At the present time, members of Congress include businessmen, farmers, teachers, and especially lawyers. In general, senators are better known than representatives because they are fewer in number and serve for a longer time. Many American presidents served in Congress before they became president.
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